Equipment for monitoring the electrodermal skin response using an embedded system based on soft processor NIOS II

Abstract

This paper presents the building results of an equipment to measure the skin resistance through a time period based on Electrodermal Skin Effect or Galvanic Skin Response (GSR). The GSR phenomenon allows to supervise the variation of the human skin resistance, because it changes in function of the sweat amount production, which in turn varies according to the emotion or feelings of a person at any moment, in order to evaluate his/her emotional conditions in a determined moment, measuring both its resistance and correlating. Among GSR monitor applications are devices to aid psychological treatments, or components of polygraph or lie detector. This paper includes the design and construction of a data acquisition system, and the digital processing of the acquired data is through an embedded reconfigurable system based on NIOS II microprocessor of Altera Corporation. This paper also provides results of the skin resistance variation in a sample of persons under several test cases, plus the results correlated with the intensity of their emotions.